How old is my non-kitten, non-senior cat?

Question

What do people look for when estimating the age of a cat who is full-grown and not yet obviously elderly? Both of my cats came from a shelter and the shelter's age estimates differed significantly from my vet's estimates. When I asked my vet about that she said it's hard to know and she was going on a gut feeling. And previously I had an experienced vet under-estimate a cat's age by more than five years.

I understand that cats don't develop gray hair like dogs do, and dental condition seems to depend as much on prior cleanings as on age itself. What other clues to age are there and how reliable are they?

Per request in a comment, here are photos:

        Cat #1 (at least 6)                            Cat #2 (estimated at 4-7 years)  

                    

Answer 1

Ways to know your cat's age

• Clear and very shiny eyes show that this is a cat somewhere between years 1 and 5.

Hazy spots show that your cat is over age 5, The more smeary the older the cat.

If the eyes are starting to appear to be white or milky your cat is probably closer 15-20 years old

• Cats teeth start out very white and yellow with age,

yellow with gritty deposits on bag teeth indicate a cat who is 6-10.

Teeth may begin to fall out if the cat is older

• You will start to notice as your cats get older that their fur may not lay as thick and smooth and may look at bit more spikey.

Also see : 5 Ways to Know your Cat's age